It could very well be a Space-based solar power system, like those microwave power plants found in earlier Sim City games. The concept is that a satellite collects solar energy and uses EMR of some sort, like microwaves, to transmit the energy to a ground receiver.

The concepts have been around since the 1970s and are capable of transmitting a few kilowatts of energy, so it's not too difficult to scale things up and have the system supply enough energy to address humanity's energy requirements by the time Vividred Operation happens